1. Field of the Invention
The present invention relates to an optical device having one or more light emitting means and one or more light inputting means optically connected with each other and more specifically to a technology for preventing stray light from being generated within the optical device.
2. Related Background Art
An optical device of this sort is fabricated by using a silicon substrate for example as its substrate and by forming necessary elements on the substrate by way of etching and others. Optical waveguide means such as an optical fiber is then provided on the substrate. Japanese Patent Application Laid-Open No. 2005-37885 (referred to as JP2005-37885A hereinafter) and Japanese Patent Application Laid-Open No. 2005-164886 (referred to as JP2005-164886A hereinafter) disclose exemplary optical devices as described above.
The optical device shown in FIGS. 1 through 3 of JP2005-37885A is a 2×2-type optical switch. This optical device is provided with four grooves in which optical fibers are installed in such a manner that they intersect from each other on the substrate. A movable mirror provided at a tip of a movable rod is disposed movably in the intersection where those four grooves intersect. The movable rod is supported movably by four hinges and is driven by a comb-type electrostatic actuator. The movable mirror is inserted into or is pulled out of the intersection in accordance to the move of the movable rod. The movable mirror switches optical paths (optical connecting) among the optical fibers provided respectively in the four grooves by being inserted into and pulled out of the intersection.
JP2005-164886A also discloses a 2×2-type optical switch similar to one in JP2005-37885A in FIGS. 14 and 15. This optical device is also provided with optical fibers installed respectively in four grooves formed in a cross shape on a substrate. Then, a movable mirror switches optical paths by being inserted into or pulled out of an intersection of those four grooves.
It is noted that the tip of the optical fiber is ground aslant with respect to an optical axis thereof (inclined end face is formed) in the both optical devices described in JP2005-37885A and JP2005-164886A. The inclined end face increases a return loss at a optical fiber end face and prevents influences on a light source and deterioration of signal quality.